Hbase過濾器（一）：比較過濾器API

過濾器（filter）

目錄

一：行過濾器（rowFilter）

解析：行過濾器基於rowkey來過濾數據。使用多種運算符返回符合條件的行鍵，同時過濾掉不符合條件的rowkey。

package compareFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class rowfilter {

    private Configuration configuration = null;
    private Connection connection = null;

    /*
    * 根據rowkey查詢
    */
    @Test
    public void rowfilter() throws IOException {
        System.out.print("begin\n");
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        //根據表名獲取表實體
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        //創建掃描實體
        Scan scan = new Scan();
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("name"));
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("age"));
        //創建過濾器實體
        Filter filter = new RowFilter(CompareFilter.CompareOp.LESS_OR_EQUAL,new BinaryComparator(Bytes.toBytes("row3")));
        //將filter實體放入掃描實體
        scan.setFilter(filter);
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
            String name = Bytes.toString(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("name")));
            Integer age = Bytes.toInt(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("age")));
            System.out.println(name);
            System.out.println(age);
        }
        resultScanner.close();
        table.close();
        System.out.print("end\n");
    }

    /*
    * 根據rowkey正則表達式查詢
    */
    @Test
    public void rowRegexfilter() throws IOException {
        System.out.print("begin\n");
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        //根據表名獲取表實體
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        //創建掃描實體
        Scan scan = new Scan();
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("name"));
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("age"));
        //創建過濾器實體
        Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new RegexStringComparator(".3"));
        //將filter實體放入掃描實體
        scan.setFilter(filter);
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
            String name = Bytes.toString(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("name")));
            System.out.println(name);
        }
        resultScanner.close();
        table.close();
        System.out.print("end\n");
    }

    /*
    * 根據rowkey字符串查詢
    */
    @Test
    public void rowSubStringfilter() throws IOException {
        System.out.print("begin\n");
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        //根據表名獲取表實體
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        //創建掃描實體
        Scan scan = new Scan();
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("name"));
        //添加掃描的列族 參數1.列族 參數2.列名
        scan.addColumn(Bytes.toBytes("cf1"),Bytes.toBytes("age"));
        //創建過濾器實體
        Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new SubstringComparator("3"));
        //將filter實體放入掃描實體
        scan.setFilter(filter);
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
            String name = Bytes.toString(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("name")));
            System.out.println(name);
        }
        resultScanner.close();
        table.close();
        System.out.print("end\n");
    }
}

二：列族過濾器（FamilyFilter）

解析：列族過濾器於行過濾器相似，不過它是通過比較列族而不是比較rowkey來返回結果的。通過使用不同組合的運算符和比較器，用戶可以在列族一級篩選所需的數據。

package compareFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class familyfilter {

    private Configuration configuration = null;
    private Connection connection = null;

    /*
    * 根據列族查詢
    */
    @Test
    public void familyfilter() throws IOException {
        System.out.print("begin\n");
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        //根據表名獲取表實體
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        //創建掃描實體
        Scan scan = new Scan();
        //創建過濾器實體
        Filter filter = new FamilyFilter(CompareFilter.CompareOp.LESS,new BinaryComparator(Bytes.toBytes("cf2")));
        //將filter實體放入掃描實體
        scan.setFilter(filter);
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
            String name = Bytes.toString(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("name")));
            System.out.println(name);
        }
        Get get = new Get(Bytes.toBytes("row1"));
        get.setFilter(filter);
        Result result = table.get(get);
        System.out.println("result:"+result);
        resultScanner.close();
        table.close();
        System.out.print("end\n");
    }
}

三：列名過濾器（QualifierFilter）

解析：使用列名進行篩選的類似邏輯，這種操作可以幫助用戶篩選特定的列。

package compareFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.BinaryComparator;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.QualifierFilter;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class qualifierfilter {


    private Configuration configuration = null;
    private Connection connection = null;
    /*
    * 根據列名查詢
    */
    @Test
    public void familynamefilter() throws IOException {
        System.out.print("begin\n");
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        //根據表名獲取表實體
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        //創建掃描實體
        Scan scan = new Scan();
        //創建過濾器實體
        Filter filter = new QualifierFilter(CompareFilter.CompareOp.LESS_OR_EQUAL,new BinaryComparator(Bytes.toBytes("age")));
        //將filter實體放入掃描實體
        scan.setFilter(filter);
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
            String name = Bytes.toString(result.getValue(Bytes.toBytes("cf1"),Bytes.toBytes("name")));
            System.out.println(name);
        }
        Get get = new Get(Bytes.toBytes("row1"));
        get.setFilter(filter);
        Result result = table.get(get);
        System.out.println("result:"+result);
        resultScanner.close();
        table.close();
        System.out.print("end\n");
    }
}

四：值過濾器（ValueFilter）

解析：這個過濾器可以幫助用戶篩選某個特定值得單元格，與RegexStringComparator配合使用，可以使用功能強大的表達式來進行篩選，需要注意的是，在使用特定比較器的時候，只能與部分運算符配合使用。

package compareFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.SubstringComparator;
import org.apache.hadoop.hbase.filter.ValueFilter;
import org.junit.Test;

import java.io.IOException;

public class valuefilter {

    private Configuration configuration = null;
    private Connection connection = null;

    /*
    * 根據值查詢
    */
    @Test
    public void valueFilter() throws IOException {
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        Scan scan = new Scan();
        Filter filter = new ValueFilter(CompareFilter.CompareOp.EQUAL,new SubstringComparator(".4"));
        //創建掃描返回類
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            for (KeyValue kv :result.raw())
            {
                System.out.println(kv);
                System.out.println(kv.getValue());
            }
        }
        resultScanner.close();
        table.close();
    }
}

五：參考列過濾器（DependentColumnFilter）

           解析：DependentColumnFilter主要根據所選列的時間戳的時間過濾所要查詢的數據

此過濾器提供了四種構造函數：

（1）DependentColumnFilter()

（2）DependentColumnFilter(byte[] family,byte[] qulifier)

（3）DependentColumnFilter(byte[] family,byte[] qulifier，boolean dropDependentColumn)    

（4）DependentColumnFilter(byte[]family,byte[]qulifier，boolean dropDependentColumn，CompareOp valueCompareOp, WritableByteArrayComparable valueComparator)

相關參數：

boolean dropDependentColumn -- 決定參考列被返回還是丟棄，爲true時表示參考列被返回，爲false時表示被丟棄

CompareOp valueCompareOp --  比較運算符

WritableByteArrayComparable valueComparator --  比較器

package compareFilter;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.Test;

import java.io.IOException;

public class valuefilter {

    private Configuration configuration = null;
    private Connection connection = null;

    /*
    * 根據參考列查詢
    */
    @Test
    public void valueFilter() throws IOException {
        //創建Hbase配置文件
        configuration = HBaseConfiguration.create();
        //創建連接
        connection = ConnectionFactory.createConnection(configuration);
        Table table = connection.getTable(TableName.valueOf("ns1:t1"));
        Scan scan = new Scan();
        Filter filter = new DependentColumnFilter(Bytes.toBytes("cf1"),Bytes.toBytes("name"),false);
        //創建掃描返回類
        scan.setFilter(filter);
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result:resultScanner){
            System.out.println(result);
        }
        resultScanner.close();
        table.close();
    }
}

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